Well all this talk about ticking noises in engines got me to wondering about my truck..
My truck; '99 K1500 327 produces a ticking type sound when underload. I does it after the motor is warm, I'll watch to see if it does it when cold also.. To me it sounds like what I've always been told is lifters, but I'm wondering if it's not pinging or knocking. I can diffently hear it in the cab while driving and the engine in under load.. I have not tried to use a higher octane gas yet, but i'm kinda leaning towards trying that. Also i am open to any other suggestions yall might have.
If it is pinging or knocking you would lose alot of power in take off and in going uphill. If you notice possible power loss then it would be your piston, if knocking, if its pinging, I think it would be your piston rod or your lifters sticking which would load down the engine alot causing it to lose power.
Leaky exhaust donut will make a ticking sound under load and only under load in it's early stages of failure. Had one repl. on my '99 Yuk at 34k. Surprised me that one would go so soon but anything's possible. At least it was in warr. at the time, I hate doing exhaust work without a lift.
ah, you may have something here, I'll look into this. anyone wanna tell me how i could check this for sure? also now that i think about it, it does sound like it's just from the drivers side of the motor..
in going uphill. If you notice possible power loss then it would be your piston, if knocking, if its pinging, I think it would be your piston rod or your lifters sticking which would load down the engine alot causing it to lose power.
I can't say there is noticable power loss, when i notice it it's like after I've made a turn around a corner and i'm accelerating and your at that point where you push on the gas slowly and a little bit at a time but not enough to let the transmission downshift and really accelerate it's just kinda slowly going.. thats when i notice the ticking sound.. if you increase rpm say when the transmission does shift and you take off, it goes away. or is unnoticable.
Translate 327 back into liters. Is this the new style truck? I have to assume that it is. We've run into problems with the exhaust flange on the y-pipe (left, drivers side), being warped and it causes an exhaust leak. About the only fix is to replace the y-pipe and cat converter assembly. Fairly expensive.
Yes it's the new style truck 5.4 liter engine. and yeah I changed out the OEM cat assembly on my '96 and it cost me $450 and I did the work myself.. Is there anything that the exhaust leak could hurt bother?
Run it (outside) and stick your head under there. If you can't hear it and know it's coming from there, try feeling around it for exhaust gasses (I'd be careful, never been burnt by the gasses but there is always a first time). I had one ticking on my 85' K5 and I just welded the shit out of it. Never got rid of the leaking completely, but the ticking stopped. I suggest if it looks like you will be able to get it apart (mine didn't) that you actually fix it the correct way....
Just curious, if it only makes noise under load how's he going to hear it in his driveway? Also, "feeling" for exhaust gasses around a 300* exhaust pipe is useless...............
I was going to suggest the donut gasket myself Adair. Ignore moron's posting telling you to listen for it and feel for it in your driveway...........it doesn't work.
You're looking for carbon tracking around the manifold-to-y-pipe flange, or the y-pipe-to-convertor flange. Exhaust leaks will leave black skid marks in the vacinity they're leaking. To fix it, you could try just tightening them up a 1/2 turn or so, or you might just have to bite the bullet like Ian said and go for the full monty.
If it's noticeable under load it should be there all the time, just not as loud. Not feeling for heat, but moving air. Guess your old-school mech hands are too numb to feel it. I had no problem.
Thanks Doc, I'll crawl under her and look somtime. I really hope I don't have to replace the cats and y-pipe.. :/ How do I rule out other causes such as knocking, pinging, lifters.. etc.. just the power loss thing? I'm trying to pin point when and what i'm doing when i notice it. I know today I was driving with the cruise set on 40 and I started to go up a slight grade and the engine responded with about 100rpm more power and I heard it.. also noticed it a couple of other times.. and it seemed to be more steady.. but it's most noticable at between 1500 and 2000rpm underload.. anyway..
Next tank, fill er' full of 93 octane and see what happens. If the noise goes away, it was spark knock. Another good way to tell if it's an internal engine noise or external exhaust noise is to drive on a divided highway, in the lane right next to the concrete wall. If it's exhaust this'll make it really clear as it'll get about 10 times louder as it bounces off the concrete.
The left flange on these engines is flat....kind of a triangular shape to it. The right side flange is the normal style with a donut. The left side uses a weird little o-ring style seal. If you do determine that your leak if from that flat flange....you might want to try "muffler cement" on the flange before you go buying the whole y-pipe. I've used this stuff successfully.
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